Rupturable crown cap



Sept. 15, 1953 D. L. WENER 2,652,165

RUPTURABLE CROWN CAP Filed Nov. 15, 1950 IN V EN TOR.

Patented Sept. 15, 1953 UNITED "STA-res" OFFICE 'a,-s52,165 RUPTURABLE CROWN CAP David Wener, Santa Ana; Calif. Application November 13, 1950, Serial N 195,349 2 Claims. (01. zit- 46) This. invention relates to closures for bottles, jars, and like containers and more particularly relates to sealin caps of the kind having a looking flange commonly crimped upon an annular shoulder at the mouth of a container and known as crown caps.

Itis an object of my invention to provide a sealing cap which may be removed from a bottle or like container without the use of a bottle opener or other instrument.

' A further object of my invention is to provide a sealing cap which may be readily applied to a bottle by existing bottling machinery but which is destroyed by the act of removing it, so that its presence in unbroken condition is a substantial guarantee that the contents of the bottle are alsoin the condition in which they left the bottlin plant. I

. .Iam aware that others before me have sought to provide bottle caps which would attain the above ,objectivesand have utilized the tear-strip principle in the construction of their caps; that is,, they have'provided caps having indented or otherwise weakened lines of rupture defining the sides of a strip extending transversely pf the c.aps,.the removal by rupture of this strip permitting thecap to be spread and removed from the bottle. However, none of these caps of which I am'aware have met with favorable response from, the bottling industry or from the public, inspite of the reat advantage that they could be removed without using a bottle-opener, because they suffered from two great disabilities, the avoidance of either of which brought the other closer. Either thelines of rupture had to be made so weak that the cap was unsuited for sealing bottles of carbonated beverages in which a considerable internal pressure might be generated, or the lines of rupture were so strong that the cap could be torn open only by a person with strong fingers. In either'case, the person attempting to remove the cap would do well to have tough and calloused fingers, as the ruptured edges of the tear-strip were sharp and exposed, and people would inevitably plac their fingers against the tear-strip to gain leverage.

It' is" accordingly a further object of my invention to provide a sealing cap o'fthe tear-strip type in which mechanical leverage is provided for tearing the lines of rupture and in which the ruptured edges of the tear-strip are remote from a position in which they might injure the fingers of a person removing the cap.

In broad terms, I accomplish the foregoing objects and others which will become apparent asqthis'specification of'a preferred embodiment of my invention proceeds, .by-forming ona bottlecap a :tearstrip which-issubstantially radial to the cap atthe-crimped or'locking edge portion of the cap and'whichthen departs from the radial-alignment at a substantial angle and "follows a non-rectilinearcourse across the plane surface of the cap to a point 'diametrically opposite to its starting point. A handle or tab is provided for the tear-strip;'which may-extend radially to thecap or may; being thin and pliable, be folded across the top of the cap or down the side-of the bottle-neck, or be twisted and moved to other positions relatively to the tear-strip. When the tab is broughtto a position of radial extensionto the 'cap,it is angulated in relation to the pa-rtof the tear-strip traversing the cap, although lying in the sameplane, in substantially the same-relation that the handle of a sickle bears to the sickle blade. It thereby-forms a key integral with the-tear-strip, by which the tear-strip may-easily be ruptured and removed by rotation of the tab-key in the well-known manner 'in'wh-icha'separate keyis used .to open a-sardine can-or coffee can; The cap may then be spread and removed.

"In" the accompanying drawing, illustrative of a* preferred embodiment'of my invention,

' Fig-.11- .is' a perspectiveview showing my improved closure applied in sealing'position to a bottle;

f Fig; 2 is a'plauviewof the blank from which the closure is" formed;

' Fig; 3 i's'aview-similar to Fig. 1, showing how the tab is "usedes' a key'to'rupture the tearstrip'; and Eigi' 4 is an exploded'*'view showing the tearst'r'ip removed" and the"closure spread for removal.

Havingrrerence now to the details or" the drawing, "I have shown a conventional bottle filhaving an annular shoulder or' bead adjaceiit the 'rimbf the mouth of thebottle. My imprdvea crewn ea-pt has a centralcircular cap portion' Q and anannularhan'ge llfto be crimped uponth ad I in the" usual manner to provide a 'lo,ck-ing= engagement between the cap and the bottle; The ease may be'provided' with acork or -foil insert-"to' effect a better seal, but such in srts easily-rupture when the backing cap portion 9*is ruptured, and are not illustrated as being only conventional supplements to the invention.

A tear-strip I2 is formed upon the cap portion 9 by the usual manner of indentation along intended lines of rupture. As clearly shown in Fig. 2, illustrating the cap as a blank, the lines of rupture I3 and I4 which form the tear-strip I2 start at spaced marginal points I5 and I6 on the central cap portion 9 and depart from these points: at acute angles to the margin of the portion 9, and traverse the portion 9 to converge at a position I! on the opposite margin of the portion 9. Preferably, the convergent position I7 is diametrically opposite some point lying between the points I5 and I6, so that neither of the segments I8 and I9 into which the tear-strip I2 divides the circular portion 9 has an arc exceeding 180 degrees. Preferably, also, the lines of rupture I3 and I4 follow arcuate courses proximately following one side of the portion 9 and thereby define a tearstrip having a form somewhat resembling the blade of a sickle. It is not, however, requisite that the lines I3 and I4 follow any particular course, as they might be closer to or farther away from the margin of the cap portion 9 than shown; but it is advantageous for purposes of winding as hereinafter described that they be gently curved rather than sharply curved or angulated, and that for the greater part of their length they converge gradually if at all, being initially substantially parallel, to provide a tear-strip which may wind upon itself rather than twist and which is not easily torn across.

From the points I5 and I6, lines of rupture 2| and 22 are formed in the flange I0, leading directly to the nearest margin of the flange and so defining an extension 23 of the tear-strip I2 across the flange. From the flange margin of the tear-strip extension 23 there extends a handle or tab 24, the sides of which are in alignment with the lines of rupture 2| and 22. For facility in manufacture, as by a simple stamping process, the tab 24 is of one piece with the rest of the cap, but it may be added and made integral therewith as by welding. If so added, it may be of thicker material or have thickened or rounded margins to provide a more secure and comfortable grip,

When the cap 8 is crimped upon the bottle 6, the tab 24 may either be bent down in contact with the bottle-neck or be folded up in contact with the tear-strip extension 23 and then folded flatly upon the cap portion 9. In the latter position it will not interfere with stacking caps in a capping-machine.

To open a bottle closed with my improved cap, the tab 24 is brought to a position radial to the bottle as shown in Fig. 3 and then is pulled or twisted slightly in the direction to follow the course of the tear-strip I2. This initial pull or twist will exert a strain upon the line of rupture 2I before exterting it upon the line of rupture 22, and these flange-lines will rupture one after the other, requiring the application of less force than would be required to rupture them simultaneously. Once the lines of rupture have been started, they will thereafter yield more easily, and the entire operation of removing the cap is such as to induce the operator to start twisting the handle towards the tear-strip I2 instead of trying to pull loose the tear-strip extension 23 by straight upward pull. Continued twisting of the tab 24, in the generally familiar manner of rotating a can-opening key, will cause the line of rupture I 3 to start to break and then cause the line of rupture I4 to start, again giving the mechanical advantage of overcoming consecutive rather than concurrent resistances. Once the lines of rupture I3 and I4 have been started, the tear-strip I2 may easily be Wound upon itself to the position I7, and separated from the cap. The cap segments I8 and I9 may then be spread and removed from the bottle as each will engage less than degrees of arc of the bead I.

The ruptured cap 8 may not be replaced to seal the bottle, and therefore it will indicate that the bottle has been opened after being sealed. If the narrow segment I8 is simply bent back without removing the wider segment I9, sufficient rim space is available for pouring from the bottle, while the segment l9 still serves to make difficult the access of dirt or insects to the bottle.

Having now described and illustrated a preferred embodiment of my invention as an example, I wish it understood that changes and alterations falling within the scope of the appended claims are to be considered as alternative embodiments of the spirit of my invention.

I claim:

1. A rupturable crown cap for a bottle, having a disc portion and a peripheral flange, the flange having a radial tab on the margin thereof, and a tear-strip having a first portion starting at said tab and integral therewith and extending across said flange in extension of a radius of said disc portion, and having a second portion extending circuitously around the disc portion of said cap to a point diametrically opposite to said first portion and there terminating, the first and second portions of said tear-strip being joined at a sharp angle approaching a right angle.

2. As a blank for the manufacture of a crown cap: a circular disc having a circular central portion for closing the mouth of a bottle or like container, and having a marginal portion adapted to be crimped as a flange to engage the rim of said container mouth and a tab extending radially from said marginal portion, said disc having indentations forming two lines of rupture extending in alignment with the sides of said tab across said marginal portion and then extending into said central portion at a sharp angle to said tab so as to form abrupt angles of departure at the inner edge of said marginal portion and convergently, proximately following one side of said central portion to a point on the edge of said central portion diametrically opposite to said tab.

DAVID L. WENER.

References Cited in the file of this patent UNITED STATES PATENTS Netherlands June 16, 1930 

